Helmet

Abstract

A helmet comprises a protective shell, an energy absorbing layer defining an inner surface of the helmet and a shear component. The shear component extends over one or more areas of the inner surface of the helmet and has an outer surface removably coupled to the inner surface of the helmet. The shear component has a distal inner surface configured to contact a wearer's head, or to support and retain a separate comfort pad configured to contact the wearer's head. In response to an oblique impact to the helmet, the shear component undergoes internal shear to allow displacement between the helmet and the wearer's head.

We claim: 
     
       1. A helmet, comprising:
 a protective shell forming an outer surface of the helmet; 
 an energy absorbing layer defining an inner surface of the helmet, the protective shell and energy absorbing layer comprising longitudinal ribs that protrude radially inwardly and transverse ribs intersecting the longitudinal ribs at intersections, further comprising front, middle and rear ventilation openings located adiacent at least some of the intersections; 
 an integrated subassembly of a shear component and a comfort pad removably mountable to the energy absorbing layer, the integrated subassembly having a base conformable to extend along a front circumferential area of the energy absorbing layer and separated fingers extending from the base that are conformable to extend along at least two of the longitudinal ribs and border at least a first front ventilation opening, wherein
 the shear component comprises a flexible sheet of a sheet thickness with raised ribs extending from the flexible sheet in the base and fingers; and 
 the comfort pad comprises a flexible sheet generally coextensive with the shear component and arranged in a stacked configuration with the shear component, the comfort pad having openings shaped to receive the raised ribs, 
 
 wherein, in response to an oblique impact to the helmet with the integrated subassembly mounted to the energy absorbing layer, the shear component undergoes internal shear to allow displacement between the helmet and a wearer's head. 
 
     
     
       2. The helmet of  claim 1 , wherein the shear component is formed of a material having a shear modulus of GPa 0.0001 to GPa 0.03. 
     
     
       3. The helmet of  claim 1 , wherein the shear component is formed of a material having a Shore 00 durometer of 0 to 60. 
     
     
       4. The helmet of  claim 1 , wherein the shear component is formed of a material having a Shore C hardness of 10 to 25. 
     
     
       5. The helmet of  claim 1 , wherein the flexible sheet of the shear component comprises a silicone gel sheet material. 
     
     
       6. The helmet of  claim 1 , wherein the shear component comprises an injection-molded thermoplastic elastomer material. 
     
     
       7. The helmet of  claim 1 , wherein the shear component comprises a thermoplastic urethane (TPU) material. 
     
     
       8. The helmet of  claim 1 , wherein the integrated subassembly further comprises an attachment textile coextensive with and coupled to the shear component in the stacked configuration, wherein the integrated assembly is removably mountable to the energy absorbing layer with the attachment textile, and wherein the attachment textile supports the shear component and provides resistance against tearing of the shear component when the integrated assembly is flexed for mounting to and unmounting from the helmet, wherein the shear component is non-sliding relative to the comfort pad and the wearer's head on an inner side thereof and relative to the attachment textile and an outwardly adjacent portion of the helmet on an outer side thereof. 
     
     
       9. The helmet of  claim 8 , wherein the attachment textile is provided as part of an insert molded textile, and wherein the integrated subassembly is removably coupled to the energy absorbing layer by touch fastening between the attachment textile and touch fasteners at multiple locations on the energy absorbing layer. 
     
     
       10. The helmet of  claim 1 , wherein the shear component comprises a viscoelastic material. 
     
     
       11. The helmet of  claim 1 , wherein the shear component is configured such that internal shear produces a damped shear action exhibiting progressively greater force in shear without high rebound. 
     
     
       12. The helmet of  claim 1 , wherein engagement between the raised ribs of the shear component and the openings of the comfort pad reduces movement of the comfort pad relative to the shear component during shear. 
     
     
       13. The helmet of  claim 1 , wherein the raised ribs have enlarged ends larger than the openings in the comfort pad, and the enlarged ends retain the comfort pad in place against the shear component. 
     
     
       14. The helmet of  claim 1 , wherein the shear component comprises a body, and the raised ribs are formed as one piece with the body. 
     
     
       15. The helmet of  claim 1 , wherein the raised ribs are dimensioned to be recessed from an inner surface of the comfort pad when the comfort pad is in an uncompressed state. 
     
     
       16. The helmet of  claim 1 , wherein the comfort pad comprises attachment textile by which the comfort pad is removably coupled to the shear component. 
     
     
       17. The helmet of  claim 1 , wherein the at least two longitudinal ribs have respective inner surfaces positioned radially inwardly relative to surrounding areas and defining respective mounting areas for mounting the integrated subassembly to the helmet. 
     
     
       18. The helmet of  claim 17 , wherein the mounting areas are positioned radially inwardly by at least 5 mm. 
     
     
       19. The helmet of  claim 1 , further comprising a rear recess that is recessed relative to a forward area of the helmet such that the wearer's head does not contact the inner surface of the helmet within the rear recess when the helmet is worn, thereby allowing the wearer's head to rotate relative to the inner surface more readily in response to the oblique impact to the helmet. 
     
     
       20. The helmet of  claim 1 , wherein the raised ribs have enlarged distal ends. 
     
     
       21. The helmet of  claim 20 , wherein each of the openings in the comfort pad that receive the raised ribs has a chamfer shaped to accommodate one of the enlarged distal ends. 
     
     
       22. The helmet of  claim 1 , wherein the comfort pad is comprised of multiple, separated comfort pad segments, and wherein the comfort pad segments include first comfort pad segments with the openings for the raised ribs and second comfort pad segments without any openings. 
     
     
       23. A helmet, comprising:
 a protective shell forming an outer surface of the helmet; 
 an energy absorbing layer defining an inner surface of the helmet, the protective shell and energy absorbing layer comprising longitudinal ribs that protrude radially inwardly and transverse ribs intersecting the longitudinal ribs at intersections, further comprising front, middle and rear ventilation openings located adjacent at least some of the intersections; 
 an integrated subassembly of a shear component and a comfort pad removably mountable to the energy absorbing layer, the integrated subassembly having a base conformable to extend along a front circumferential area of the energy absorbing layer and separated fingers extending from the base that are conformable to extend along at least two of the longitudinal ribs and border at least a first front ventilation opening, wherein 
 the shear component comprises a flexible sheet of a sheet thickness with raised ribs extending from the flexible sheet in the base and fingers, wherein the raised ribs have enlarged distal ends; and 
 the comfort pad comprises a flexible sheet generally coextensive with the shear component and arranged in a stacked configuration with the shear component, the comfort pad having openings for the raised ribs shaped smaller than the enlarged distal ends of the raised ribs, wherein the enlarged distal ends can be forcibly passed through the openings to secure the comfort pad in position relative to the shear component, 
 wherein, in response to an oblique impact to the helmet with the integrated subassembly mounted to the energy absorbing layer, the shear component undergoes internal shear to allow displacement between the helmet and the wearer's head. 
 
     
     
       24. The helmet of  claim 23 , wherein the shear component is formed of a material having a shear modulus of GPa 0.0001 to GPa 0.03. 
     
     
       25. The helmet of  claim 23 , wherein the shear component is formed of a material having a Shore 00 durometer of 0 to 60. 
     
     
       26. The helmet of  claim 23 , wherein the shear component is formed of a material having a Shore C hardness of 10 to 25. 
     
     
       27. The helmet of  claim 23 , wherein the shear component comprises a silicone gel sheet material. 
     
     
       28. The helmet of  claim 23 , wherein the shear component comprises an injection-molded thermoplastic elastomer material. 
     
     
       29. The helmet of  claim 23 , wherein the shear component comprises a thermoplastic urethane (TPU) material. 
     
     
       30. The helmet of  claim 23 , wherein the integrated subassembly further comprises an attachment textile coextensive with and coupled to the shear component in the stacked configuration, wherein the integrated assembly is removably mountable to the energy absorbing layer with the attachment textile, and wherein the attachment textile supports the shear component and provides resistance against tearing of the shear component when the integrated assembly is flexed for mounting to and unmounting from the helmet, wherein the shear component is non-sliding relative to the comfort pad and the wearer's head on an inner side thereof and relative to the attachment textile and an outwardly adjacent portion of the helmet on an outer side thereof. 
     
     
       31. The helmet of  claim 30 , wherein the attachment textile is provided as part of an insert molded textile, and wherein the integrated subassembly is removably coupled to the energy absorbing layer by touch fastening between the attachment textile and touch fasteners at multiple locations on the energy absorbing layer. 
     
     
       32. The helmet of  claim 23 , wherein the shear component comprises a viscoelastic material. 
     
     
       33. The helmet of  claim 23 , wherein the shear component is configured such that internal shear produces a damped shear action exhibiting progressively greater force in shear without high rebound. 
     
     
       34. The helmet of clairn  23 , wherein engagement between the raised ribs of the shear component and the opening of the comfort pad reduces movement of the comfort pad relative to the shear component during shear. 
     
     
       35. The helmet of  claim 23 , wherein the opening comprises a chamfer shaped to accommodate the enlarged distal ends of the raised ribs. 
     
     
       36. The helmet of  claim 23 , wherein the shear component comprises a body having a width selected to compliment to a width of the comfort pad, and the raised ribs are formed as one piece with the body. 
     
     
       37. The helmet of  claim 23 , wherein the raised ribs are dimensioned to be recessed from an inner surface of the comfort pad when the comfort pad is in an uncompressed state. 
     
     
       38. The helmet of  claim 23 , wherein the comfort pad comprises attachment textile by which the comfort pad is removably coupled to the shear component. 
     
     
       39. The helmet of  claim 23 , wherein the at least two longitudinal ribs have respective inner surfaces positioned radially inwardly relative to surrounding areas and defining respective mounting areas for mounting the integrated subassembly to the helmet. 
     
     
       40. The helmet of  claim 39 , wherein the mounting area are positioned inwardly by at least 5 mm. 
     
     
       41. The helmet of  claim 23 , further comprising a rear recess that is recessed relative to a forward area of the helmet such that the wearer's head does not contact the inner surface of the helmet within the rear recess when the helmet is worn, thereby allowing the wearer's head to rotate relative to the inner surface more readily in response to the oblique impact to the helmet. 
     
     
       42. The helmet of  claim 23 , wherein the comfort pad is comprised of multiple, delineated comfort pad segments, and wherein the comfort pad segments include at least one first comfort pad segment with one of the openings for the raised ribs and at least one second comfort pad segment without any opening.